If we talk about original Leica to Russian Leica , Russian one makes a sharp gear noise like an Messerschmitt , I think with an Mercedes engine , Original Leica TM makes a smoother , more smooth bokeh sound like a Spitfire with an Rolls Royce engine.

Nice analogy. When I press the shutter on my Leica II, which was made in 1932, it sounds like an insects whisper.